Bought a t shirt at a show last night (size medium from Mormon) and it is TINY!! Just tried it on and it is really tight, I normally can fit into a regular small t shirt from other shows no bother but this is a lt smaller and it's a medium!
What are the chances they would exchange for a large if I took it in? Selling that t shirt as a medium is false, I'm really quite skinny, would hate to see a small one
Sizing is based on the style and cut of the shirt. Sounds like you bought a babydoll cut.
If the merch manager's a decent person, they might exchange it. But really its (hate to say it) your responsibility to hold up the shirt and make sure it looks right before you walk out of the theatre.